Automatic lathe



Dc. 27, 1949 A. BECHLER AUTOMATIC LATHE Filed sept. 2o, 41946 11,/ lll/IIIA Patented Dec. 27, -1949 UNITED STATES PATENT OFFICE Application september 20, 1946, serial. Naceaiefi In Switzerland May3, 19,46

4 claims. (ci. s2-f2s) There exist automatic lathes with movable headstock moving in a plane parallel to the live spindle axis, the chuck of lwhich is driven by a gear-wheel. The positive transmission between the driver and the chuck is constituted by laterally arranged gears, that is not only cumbersome but limits the number of uses of the lathe in question.

In the automatic lathe according to the present invention, an idle gear .wheel situated beneath the headstock transmits the rotary motion of the driver to the chuck. The headstock can be `displaced longitudinally, taking with it a sliding gear consisting of a pinion engaging with the idle wheel. The sliding gear is `drawn along by means of discs cooperating in rolling contact along a line coinciding with the pitch circles of the respective wheels.

The attached dnawing represents, by way of eX- ample, two embodiments of the screw cutting lathe according to the invention.

Fig. 1 is a side-elevation of the lathe, seen partly in section.

Fig. 2 is an end view of the same, seen in section along the line II-II in Fig. 1.

Fig. 3 is a view of a 'part of the lathe shown in Fig. 1.

Fig. 4 is a side-elevation, seen partly in section, of la second embodiment of the invention.

With reference to Figs. 1, 2 and 3, the iframe or bed of the lathe is denoted by I; along the upper surface of the bed a headstock 3 is capable of moving in a plane parallel to the live spindle. The motion of the headstock is directed by a cam wheel not represented of construction familiar to specialists.

Lying in a perpendicular plane passing through the chuck, a shaft 5 is carried in bearings in the bed of the lathe and is driven by a pulley 6. This shaft is provided with la longitudinal slot 1 in |a certain portion of its length. along which a cotter 8, planted in the hub of the sliding gear, can move, to form a sliding coupling. The sliding gear is driven by the pulley 6 and thus imparts rotary motion to the chuck 4, for the turning of the bar Iii from `which the pieces are formed. The motion is transmitted to the live spindle through the medium of a pinion II in mesh with an intermediary pinion I2, constituting the idlewheel, turning on its axle I3 screwed in the headstock 3. The intermediary pinion I2 drives the helical gear wheel I4, keyed to the live spindle 4. The pinion II is solid with two discs I5 of the same diameter, between whicha third disc I 6 solid with the intermediary pinion I2 turns. These parts II, I2, I5 and I8 are shown more clearly in 55 2 Fig'. 3 from which it can be seen that the discs I5 come into contact with the third disc I6 along the line coinciding with the pitch circles of the two pinions II and I2. In this way there results little or no friction between these revolving lparts.

The shaft 5 extends to the front of the lathe and is pivoted in the frame or bed at Il; it carries :a pinion I5 close to the bearing in mesh with an idle wheel I9 pivoted to the support 20 for the work guide bushing 22, and engaging with another pinion 2l integral with the cannon through which the bar III from which the pieces are formed passes, so that this work guide bushing turns at the same speed as the chuck 4.

When the lathe is running, the tools presented from the sides 23 moves to the work at the free end of the work guide bushing 22. 'The headstock, whose motion is directed by a cam wheel not represented, moves along the bed of the lathe, taking withit the idle wheel I2 With Vdisc AIii cooperating With the discs I5, in such a manner that the sliding gear 9 is drawn :along the shaft 5. Whatever may be the position of the sliding gear, the latter is Imade to turn in virtue of the coupling formed by the cotter 8 cooperating with the slot 1.

In the embodiment represented in Fig. 4, most of the parts described above are to be found. But in this case the idle wheel I 2 is in continuous mesh with a long pinion 24 keyed to the shaft V5 and driven by the pulley l6. Clearly, the motions of the head-stock 3 along the bed 2 supported by the frame I have no iniluence lon the positive transmission between the shaft 5 and the chuck 4, for the teeth of the idle wheel I2 slip Within those of the long pinion 24. In this particular case, it is however impossible to provide the pinions with helical teeth as can be done in the embodiment shown in Figs. 1 and 2.

In both embodiments, the intermediary pinions, serving as idle wheels, could also be replaced lby a number of gears or idle wheels.

What I claim is:

1. In an automatic lathe, a base, a rotatable spindle, a headstock carrying said spindle and being mounted on said base slidably in a direction parallel to said spindle, a spindle-drive shaft mounted on said base at a place beneath said headstock, a gear Wheel on said spindle, a sliding gear mounted on said spindle-drive shaft displaceably in longitudinal direction of the latter, an idle gear means mounted on said slidable headstock, in engagement with said gear wheel and said sliding gear to rotate said spindle by said spindle-drive shaft, a coupling means fixed to said sliding gear, and a coupling part xed to 3 said idle gear means and engaging said coupling means to displace said `sliding gear longitudinally on a displacement of said headstock.

2. In an automatic lathe, a base, a rotatable spindle, a headstock carrying said spindle and being mounted on said base slidably in a direction parallel to ysaid spindle, a spindle-drive shaft mounted on said base at a place beneath said headstoclg, aV gear,i wheel on said spindle, a sliding gear mounted on Said spindle-drive shaft. dise placeably in longitudinal direction of the latter, an idle gear wheel mounted on said slidable head-f. stock, in drive connection with said gear wheel and said sliding gear to rotate said spindle by said spindle-drive shaft, two discs @ged c Qaxially; to said sliding gear, another disc entering between said two discs, xed coax-ially to said idiie gear wheel and in engagement with the discs of said sliding gear along circles equal in diariaetery to the pitch circles of said sliding gear and said idle gear wheel to displace seid Sliding gear longitudinally on e. displacement of 'said siidable headstooli.

Si.r 1n. an automatic lathe,l e bese. a rotatable sninfil'el e. heedstook carrying. Seid Spindle and being mounted onseid bese. slidobly in. e. direction nataliel. to seid spindle., a. Spindle-.finge ,shaft with itsv exis. vertical beneath end parallel. to. the exis of Said spin e, mounted on seid. basse, at a piece beneath. Sr` heedstook and provided. with e longitudinal groove a geen Wheel on. Seid Sninnle, e. Sliding eeer mounted siidebly on sein spindle,- drive enen. anni. having. e. eoupiing, pin entering Said gtoove an idle gear wheelV mounted on, `sind eiidaiole neadstook. in engagement with Seid. gear Wneei and` Said sliding gear to, rotate said spin eie by Seid. spindle-drive shaft two dises nxed eo.- axially to,y said, sliding gear at a distance from eeen othen another dise. entering between Said two dises fixed eoaxiellytoX said idle gear wheel parallel to said spindle, a supportv mounted onr dal@ base, a rotatable work guide mounted on said support, a spindle-drive shaft mounted on said base at a place beneath said headstock and Yextending to beneath said support, gear transmission means connecting said spindle-drive sha-it, with said work-guide to rotate the latter by said spindle-drive shaft, a gear wheel on said spindle., a sliding gear mounted on said spindledrive shaft displaceably in longitudinal direction ci the latter, idle gear means mounted on said slidable headstock, in engagement with said gear wheel and said sliding gear torotate said spindle by said spindle-drive shaft, a coupling means xed to said sliding gear and a coupling part iixned to said idle gear means and engaging said coupling means to displace said sliding gear longitudinally on a displacement ofV said head'- Stol..

ANDR BYEcH-LER,

REFERENCES CITED 'ljhe following references are of record in the @le of; this patent:

UNITED STATES PATENTS Number- Name Date 1.95 085 Brigham Y V Y Sept. l1, 18,77 1,952,966 Bechler Mar. 27., 1934 2,288,578, Yeomans a Junel 30, 1942 agit-9,963 Wilson May 25,/ 1943 2,395,365 Wilson l Feb. 1,9, 1946 

